Lithium aluminosilicate glass

Figure 6.26. A. O MQMAS NMR spectra of albite glass, showing the data presented in both direct double FT and sheared format, with the observed and simulated one-dimensional slices below. From Dirken et al. (1997), by permission of the copyright owner. B. Isotropic projections of the triple-quantum MAS spectrum of sodium aluminosilicate and lithium aluminosilicate glasses. From Lee and Stebbins (2000), by permission of Elsevier Science.

BMAS - barium-magnesium-aluminosilicate glass ceramic LAS - lithium-aluminosilicate glass ceramic)... 

Varshneya AK, Spinelli IM. High-strength, large-case-depth chemically strengthened lithium aluminosilicate glass. American Ceramic Society Bulletin, 2009 88(5) 27-32. 

Commercial lithium aluminosilicate glass-ceramics provide excellent examples of such behavior. The initial glass used for production of transparent cookware, for example, has a thermal expansion coefficient of 4 ppm K , Tg 730 °C, and T = 760 °C. After processing, the thermal expansion coefficient is == 0.5 ppm K and Tg and T can no longer be detected on an expansion curve below 1000 °C. Heat treatment results in the formation of a lithium aluminosilicate crystal which has a very low thermal expansion coefficient. Removal of lithium from the residual glassy phase also decreases the thermal expansion coefficient of that phase, while simultaneously increasing the transformation and softening temperatures. 

C. E. Lord, in Crystallization and Properties of Lithium Aluminosilicate Glass-Ceramics, M.S. Thesis, Alfred University, 1995. 

Lithium-aluminosilicate glass ceramics Supports for telescope mirrors... 

Lapp, J. S. and Shelby, J. E. (1987) The Mixed Alkali Effect in Lithium Aluminosilicate Glasses, J. Non-Cryst. Solids, 95-96, 889-896. 

They were able to fit experimental modulus data for a calcium-potassium nitrate melt and a lithium aluminosilicate glass using a double lognormal distribution function. 

Rgure 6.10 Scanning electron micrograph of a crystallized lithium aluminosilicate glass after etching in HF. ... 

Maier V. and Muller G., "Mechanism of Oxide Nucleation in Lithium Aluminosilicate Glass-Ceramics," / Am. Ceram. Soc., 70 C, 176-178 (1989). 

Sarno R.D., Tomozawa M., "Toughening Mechanisms for Zirconia—Lithium Aluminosilicate Glass-Ceramic,"/. Mater. Sci., 30, 4380-88 (1995). 

Yamane M., Aso S., Okano S., Sakaino T. Low temperature synthesis of a monolithic silica glass by the hydrolysis of a silica gel. J. Mater. Sci. 1979 14 607-611 Yang J.-S., Sakka S., Yoko T., Kozuka H. Preparation of lithium aluminosilicate glass-ceramic monolith from metal-alkoxide solution. Part I. Preparation and properties ofprecursor gel monolith. J. Mater. Sci. 1990 25 1773-1778... 

Another compositional and application area where the concept of powderless bulk gel -> bulk ceramics has been successfully employed is low-thermal expansion lithium aluminosilicate glass-ceramics from gels (Yang et al., 1990, 1991). The selected oxide composition was Li20 Al203-4Si02. 

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